Top-hung sliding doors and windows are well known. The doors or windows are suspended from rollers attached to the top rail of the door or window which ride on a track mounted to the top jamb of the door or window opening. The bottom rail of the door or window is usually supported and guided by spring-loaded rollers which ride within a track in the bottom sill of the window opening. The height of the doors or windows closely approximates the height of the opening so as to minimize the gap between the bottom rail of the door or window and the sill.
On occasion, top-hung doors or windows may be installed in applications where the top jamb of the opening is subject to downward deflection. An example would be sliding doors or windows in a luxury suite or "sky box" at a stadium, where the weight of spectators in the deck above may cause the top jamb to deflect downward by one half to three-quarters of an inch.
Such applications are problematic with regard to the spacing between the bottom rail of the door or window and the sill. To accommodate deflection of the upper edge of the window opening when subjected to live loads, it is necessary to leave a gap of nearly an inch between the bottom rail of the door or window and the sill. Concealing such a large gap is usually done in one of two ways. First, weathering can be installed which extends sufficiently far above the bottom track to cover the gap. A drawback to this approach is that when the sliding door is open, the tall weathering presents an obstacle which can trip persons passing through the doorway. In addition, such tall weathering is aesthetically displeasing. A second approach is to recess the bottom track into the threshold or sill by a distance sufficient to eliminate gaps between the bottom rail of the door and the threshold, or between the window and the sill. While this approach eliminates the problem of weathering projecting above the threshold, the deep track opening is aesthetically undesirable. Further, the deep track opening collects dirt and trash which can be difficult to remove.
Thus there is a need for a top-hung sliding door or window which can accommodate live loads without creating an undesirable gap between the bottom rail of the door or window and the adjacent threshold or sill.
There is a further need for a top-hung sliding door or window which can accommodate live loads without requiring undesirably tall weathering to conceal the gap between the bottom rail of the door or window and the adjacent threshold or sill.
There is a still further need for a top-hung sliding door or window which can accommodate live loads without requiring a deep track to conceal the gap between the bottom rail of the door or window and the adjacent threshold or sill.